pg_upgrade: conditionally create cluster delete script

If users create tablespaces inside the old cluster directory, it is
impossible for the delete script to delete _only_ the old cluster files,
so don't create a script in that case, and issue a message to the user.

diff --git a/contrib/pg_upgrade/check.c b/contrib/pg_upgrade/check.c
index a7d4a68ce3caa1fa761cc33d79edce88b604f622..65fb54829e3436a469afc22796854f48fb72bdeb 100644 (file)
--- a/contrib/pg_upgrade/check.c
+++ b/contrib/pg_upgrade/check.c
@@ -246,10 +246,17 @@ output_completion_banner(char *analyze_script_file_name,
        "by pg_upgrade so, once you start the new server, consider running:\n"
               "    %s\n\n", analyze_script_file_name);
 
-   pg_log(PG_REPORT,
-          "Running this script will delete the old cluster's data files:\n"
-          "    %s\n",
-          deletion_script_file_name);
+
+   if (deletion_script_file_name)
+       pg_log(PG_REPORT,
+              "Running this script will delete the old cluster's data files:\n"
+              "    %s\n",
+              deletion_script_file_name);
+   else
+       pg_log(PG_REPORT,
+              "Could not create a script to delete the old cluster's data\n"
+              "files because user-defined tablespaces exist in the old cluster\n"
+              "directory.  The old cluster's contents must be deleted manually.\n");
 }
 
 
@@ -584,14 +591,38 @@ create_script_for_old_cluster_deletion(char **deletion_script_file_name)
 {
    FILE       *script = NULL;
    int         tblnum;
+   char        old_cluster_pgdata[MAXPGPATH];
 
    *deletion_script_file_name = pg_malloc(MAXPGPATH);
 
-   prep_status("Creating script to delete old cluster");
-
    snprintf(*deletion_script_file_name, MAXPGPATH, "delete_old_cluster.%s",
             SCRIPT_EXT);
 
+   /*
+    *  Some users (oddly) create tablespaces inside the cluster data
+    *  directory.  We can't create a proper old cluster delete script
+    *  in that case.
+    */
+   strlcpy(old_cluster_pgdata, old_cluster.pgdata, MAXPGPATH);
+   canonicalize_path(old_cluster_pgdata);
+   for (tblnum = 0; tblnum < os_info.num_old_tablespaces; tblnum++)
+   {
+       char        old_tablespace_dir[MAXPGPATH];
+       
+       strlcpy(old_tablespace_dir, os_info.old_tablespaces[tblnum], MAXPGPATH);
+       canonicalize_path(old_tablespace_dir);
+       if (path_is_prefix_of_path(old_cluster_pgdata, old_tablespace_dir))
+       {
+           /* Unlink file in case it is left over from a previous run. */
+           unlink(*deletion_script_file_name);
+           pg_free(*deletion_script_file_name);
+           *deletion_script_file_name = NULL;
+           return;
+       }
+   }
+
+   prep_status("Creating script to delete old cluster");
+
    if ((script = fopen_priv(*deletion_script_file_name, "w")) == NULL)
        pg_log(PG_FATAL, "Could not open file \"%s\": %s\n",
               *deletion_script_file_name, getErrorText(errno));